The Boolean and CHAR Types

Many things can be expressed in terms of two mutually exclusive states. For example, either I am at home or I am not; either I have enough money to buy the latest Porsche or I have not. It is therefore important to be able to define variables which can take precisely two values. Such variables are called logical variables or boolean variables (after the mathematician George Boole). In MODULA-2 there is a predefined type BOOLEAN. Any variable of type BOOLEAN can take one of the two values FALSE or TRUE, where FALSE and TRUE are standard identifiers.